RNA plymerase will be isolated from log phase cells, sporulating cells, and spores of Bacillus subtilis. The enzymes isolated from these various stages will be analyzed for their subunit compositions and template specificities. Furthermore the conformation of their active sites will be analyzed by NMR techniques to determine whether modified RNA polymerase molecules can be distinguished by differences in conformation. RNA polymerase from RNA polymerase mutants will also be compared to the wild type enzyme to see whether there is a lack of interaction with effectors or whether there is a conformational change near the active site. Various DNA-binding proteins which are produced during sporulation will also be tested for their effects on RNA polymerase activity. The properties of the RNA polymerase from rifampin-resistant sporulation-temperature-sensitive mutants will be analyzed to determine whether there is a sequential change in the RNA polymerase structure during sporulation. Furthermore the mRNA synthesized by these conditionally asporogenousmutants will beanalyzed to determine whether a few or many gene products are missing; for this purpose RNA-DNA hybridization techniques will be used. These studies should give some understanding to the role of RNA polymerase structure and function during differential gene transcription. Also the role of effectors may be determined by examininging the sequentially blocked RNA polymerase mutants.